

package com.hazelcast.map.impl;

import com.hazelcast.internal.services.SplitBrainProtectionAwareService;
import com.hazelcast.internal.util.ConstructorFunction;
import com.hazelcast.internal.util.ContextMutexFactory;

import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.ConcurrentMap;

import static com.hazelcast.internal.util.ConcurrencyUtil.getOrPutSynchronized;

/**
 * Split brain protection service will ask map service about whether map has defined split brain protection or not.
 */
public class MapSplitBrainProtectionAwareService implements SplitBrainProtectionAwareService {

    private static final Object NULL_OBJECT = new Object();

    private final MapServiceContext mapServiceContext;

    private final ConcurrentMap<String, Object> splitBrainProtectionConfigCache = new ConcurrentHashMap<>();
    private final ContextMutexFactory splitBrainProtectionConfigCacheMutexFactory = new ContextMutexFactory();
    private final ConstructorFunction<String, Object> splitBrainProtectionConfigConstructor = new ConstructorFunction<>() {
        @Override
        public Object createNew(String name) {
            MapContainer mapContainer = mapServiceContext.getMapContainer(name);
            String splitBrainProtectionName = mapContainer.getSplitBrainProtectionName();
            return splitBrainProtectionName == null ? NULL_OBJECT : splitBrainProtectionName;
        }
    };

    public MapSplitBrainProtectionAwareService(MapServiceContext mapServiceContext) {
        this.mapServiceContext = mapServiceContext;
    }

    @Override
    public String getSplitBrainProtectionName(String name) {
        Object splitBrainProtectionName = getOrPutSynchronized(splitBrainProtectionConfigCache, name, splitBrainProtectionConfigCacheMutexFactory, splitBrainProtectionConfigConstructor);
        return splitBrainProtectionName == NULL_OBJECT ? null : (String) splitBrainProtectionName;
    }

    public void onDestroy(String name) {
        splitBrainProtectionConfigCache.remove(name);
    }
}
